1. Field of the Invention
The present invention relates to a patient transfer system, and more particularly to a patient lifter device that also emits heated or cooled air that surrounds a patient resting thereon, maintaining desired body temperature during surgery.
2. Description of the Prior Art
The lateral transfer of patients, especially in the operating room, can be a difficult and poorly controlled procedure. Not only can the patient be injured during the process, but lateral patient transfer often contributes to back injuries incurred by hospital personnel, the most common work-related injury to hospital workers. The development of an air lifter, similar to a hovercraft, represents a significant advance in handling of patients. Making the device disposable has obvious advantages for sterility and cleanup. However, there is resistance in employing such disposable devices for single usage because of associated costs. As a result, use of disposable lateral transfer devices is generally limited to special situations, such as transporting very large patients.
Disposable intraoperative heaters are already in general use, generally employing a simple heated air blower and a light plastic “tent”. Thermal coverings have been provided. The most common alternatives are water mats, filled with heated circulating water. While effective, these mats often come apart during patient transfer, causing a veritable flood on the operating room floor, and necessitating significant cleanup.
Examples of various patient support systems and/or transporters are set forth below.
U.S. Pat. No. 3,449,776 to Brock discloses a collapsible telescoping stretcher including a plurality of flexible straps attached to the stretcher adapted to tie down the legs and torso of the patient to the stretcher. An inflatable mattress rests on the stretcher and has separate leg portions whereby the straps can be used to tie down the legs individually. A collapsible telescoping head support is mounted on the stretcher and had adjustable torso members. Straps extend through the head support and torso members for immobilizing a broken neck. The stretcher does not provide a patient lifter having heated/cooled air released from a top chamber. Further, there is no discharge of air on the bottom surface of the stretcher enabling the creation of an air cushion that facilitates the lateral movement of a patient.
U.S. Pat. No. 3,644,950 to Lindsay et al. discloses a patient support system. Included with the system is a bed for supporting and treating a hospital patient. A lamination of low and medium density plastic foam is enclosed in a pressurized container. An open pore foam layer on top of the container produces a flow of air from the top of the foam layer for patient ventilation. Control of the volume of air varies the degree of ventilation. The pressurizing air for the container is controlled to vary the relative firmness of support. The patient support of the '950 patent provides ventilation around the patient delivered through foams of different density. The ventilation air is not heated. There is no discharge of air on the bottom surface of the patent support system enabling the creation of an air cushion that facilitates the lateral movement of a patient.
U.S. Pat. No. 3,667,073 to Renfroe discloses a patient transporter. This apparatus provides for effortless moving of a non-ambulatory patient from a bed or operating table to a cart, e.g., recovery room stretcher or the like and from the cart to other non-porous surfaces, e.g., X-ray tables, etc. The patient transporter discharges compressed air through the apertures in the bottom of an inflatable mattress to levitate the mattress from an impervious stretcher or bed during lateral transport of the patient. The compressed air may be discharged from apertures provided on top of the inflatable mattress to essentially levitate the patient with burns or severe injury by a plurality of air jets. The efficacy of this system is questionable. Strong air jets may even aggravate the patient's skin injury. While the discharge of compressed air at the bottom of the inflatable mattress facilitates the lateral movement of the patient, the patient transporter does not provide heated air surrounding the patient.
U.S. Pat. No. 3,740,777 to Dee discloses a bed support. This bed support holds all or part of the human body and includes a chamber having an upper wall at least part of which is of thin flexible sheet material, e.g. rubber film, adapted when supported by gas pressure in the chamber to define a trough in which the item may lie. The body support device merely inflates balloons surrounding an individual body portion and the balloons have apertures that discharge air towards the body part through PTFE or polyethylene disks. This discharge of air through the apertures and the disk separates the balloons' external surfaces from the body part by the flow of air. No air is discharged on the bottom of the body support, with the result that a patient laying on the body support cannot be easily transported laterally. Moreover, no heated air is discharged to surround the patient and thereby provide warmth and comfort.
U.S. Pat. No. 3,757,366 to Sacher discloses a cushion for preventing and alleviating bedsores. The cushion for preventing and alleviating bedsores includes a warm air delivery system which delivers warm air in the close area of the cushion that contacts the skin of the patient, thereby preventing direct contact between the skin and the cushion and preventing or alleviating bedsores. No air is discharged below the cushion since the bottom portion of the cushion is indicated to be non-porous. Thus, the cushion with the patient laying there above may not be easily transported laterally.
U.S. Pat. No. 3,778,851 to Howorth discloses a mattress for use in treating a patient who has undergone extensive surgery or who has been severely burned. The mattress comprises an upper panel, a lower panel, and means for supplying air to the space between the two panels. The lower panel is made of air-impermeable material. At least a part of the upper panel is perforated to allow conditioned air to issue forth and pass around the patient. Since the lower portion of the mattress is indicated to be impermeable, no air is delivered in the bottom of the mattress. As a result, a patient lying on the mattress may not be easily transported laterally.
U.S. Pat. No. 3,822,425 to Scales discloses an inflatable support appliance. The inflatable support apparatus of the '425 patent has an air impermeable base with air impermeable protrusions to which an air permeable cap is mounted. A person supported by these caps receives air through the apertures provided in the cap, preventing direct contact between the person and the cap. No air is delivered at the bottom, since the base and the protrusions are air impermeable. As a result, when a patient is supported by the caps, the lateral movement of the patient is very difficult, if not impractical.
U.S. Pat. No. 4,279,044 to Douglas discloses a fluid support system for a medical patient. No air is delivered around the patient and no air is released on the bottom of the support system. The lateral movement of the patient from a stretcher to an operating system is not facilitated.
U.S. Pat. No. 4,391,009 to Schild et al. discloses a ventilated body support. This ventilated support for living bodies comprises an inflatable alternating pressure pad, which is either enclosed by or forms a part of an air permeable plenum chamber through which air is pumped at low pressure to provide a source of ventilating air to a body resting on the support. The alternating pressure pad which is inflated by a high pressure pump has two sets of inter-digitized cells which are alternately inflatable and deflatable and carry the weight of a body alternately, on each of the two sets of cells. The disclosed ventilated body support has a plurality support tubes comprising a high pressure central sealed portion and a low pressure surrounding portion each pressurized by two tubes with individual valves from a pump. The two portions may bleed air to the environment to adjust the support character of the ventilated body support. Heated air is not released to surround the patient. No air is released in the bottom of the ventilated body support and a patient lying on the ventilated body support may not be easily transported laterally.
U.S. Pat. No. 5,022,110 to Stroh discloses a low air loss mattress. The low air loss mattress is made of multiple cushions, which are connected together and form an integral mattress which may be used on a standard hospital bed. The multiple cushions allow for variable pressure to support a patient and to compensate for different weights of various portions of the body of the patient. Each cushion is provided with air vents in its upper surface to provide air circulation around a patient and for pressure regulation in each cushion. The air may be heated. Retainers are provided to prevent billowing of each cushion in its center portions and maintain a substantially level patient support surface. A small portable blower provides a constant air supply for each of the cushions and allows adjustment of the air pressure in each of the cushions to accommodate varying weights of patients on the mattress. Any release of air occurs only on the patient contacting surface, and the air may be heated. There is no discharge of air on the bottom of the low air loss mattress, which does not function as a transfer device.
U.S. Pat. No. 5,109,560 to Uetake discloses a ventilated air mattress with alternately inflatable air cells having communicating upper and lower air chambers. The ventilated air mattress with alternately inflatable air cells has a plurality of adjacent cells. One of the cells is inflated while the adjacent cell is deflated altering the support characteristic of the air mattress at a specific body contacting location so that no individual part of the body has to support the bodyweight over a period of time. The deflating of the cell is accomplished by opening a valve and the air is not heated and is not discharged surrounding the patient. No air is discharged from the bottom surface of the ventilated air mattress and therefore, moving a patient lying on the air mattress laterally is not assisted by an air cushion.
U.S. Pat. No. 5,113,539 to Strell discloses a body supporting device such as a mattress, box spring, cushion or car seat having an inner coil spring structure. The device is provided with adjustable firmness by means of a plurality of inflatable pneumatic members. The pneumatic members are positioned within the interstices formed between adjacent coil springs in a variety of patterns. The pneumatic members are connected to an inflation control device for adjusting the firmness of the body supporting device in varying modes, including a pulsation mode to provide a messaging affect. No air is discharged from the top or bottom surface of the body supporting device. Moving a patient lying on the air mattress laterally is not assisted by an air cushion and no temperature control is achieved.
U.S. Pat. No. 5,168,589 to Stroh et al. discloses a pressure reduction air mattress and overlay. This patent is a continuation in part of U.S. Pat. No. 5,022,110, discussed above. Multiple cushions allow for variable pressure to support a patient and to compensate for different weights of various portions of the body of the patient. Each cushion is provided with air vents in its upper surface to provide air circulation around a patient and for pressure regulation in each cushion. The air may be heated. Retainers are provided to prevent billowing of each cushion in its center portions and maintain a substantially level patient support surface. A small portable blower provides a constant air supply for each of the cushions and allows adjustment of the air pressure in each of the cushions to accommodate varying weights of patients on the mattress. Any release of air occurs only on the patient contacting surface and the air may be heated. There is no discharge of air on the bottom of the low air loss mattress and it is not a transfer device. There is no air cushion under the mattress assisting this movement.
U.S. Pat. No. 5,249,318 to Loadsman discloses an air cushion support. This air inflatable support appliance has internally sealed seams, internal diaphragms and internal structural support members. The air cushion support of the '318 invention provides a flow of air between the top portion of the support and the patient lying there over requiring no cover or draw sheet. There is no discharge of air on the bottom of the air cushion support, and this device does not aid in the lateral transfer of the patient between a stretcher and an operating table.
U.S. Pat. No. 5,416,935 to Nieh discloses a surface air conditioning device including a plurality of passages through a support surface which overlies a closed volume in which temperature conditioned air is supplied; each passage is provided with a pressure actuated flow control valve which is normally closed to prevent loss of conditioned air through the associated passage; pressure contact with the valve effects opening thereof to allow conditioned air to flow through the passage. The top chamber includes partitions, barriers or coil springs located therein. Thus, the surface air conditioning device is not readily compressed to a substantially flat structure under the patient when not in use and as compressed the surface air conditioning device would be lumpy under the patient, causing discomfort. Moreover, the coiled spring obstructions require the volume of the chamber to be increased to accommodate the springs, and in turn, increased pressure is needed to achieve optimum air delivery to the patient.
U.S. Pat. No. 5,483,709 to Foster et al. discloses a low air loss mattress with rigid internal bladder and lower air pallet. It is not disposable, and is primarily thick mattress. This mattress has an upper patient supporting low air loss bladder for ventilating and preventing skin degeneration of a patient supported. It does not have any temperature control feature. Unlike the submitted device, it has an intermediate rigidly inflatable static bladder which must become relatively rigid upon inflation to aid in transferring or weighing a patient. A lower high air loss bladder is provided for reducing the friction force between the mattress and the supporting surface to facilitate surface-to-surface transfers. The high air loss bladder includes a peripheral tube, which seals against a supporting surface to contain the air, which escapes from longitudinal sacks within the tube. The foot sections of the low air loss and static bladders are selectively deflatable. The low air loss mattress has a low air loss bladder 12, an intermediate rigidly inflatable static bladder 14 and a lower high air loss bladder 18. The low air discharge bladder releases air surrounding the patient, reducing patient contact with the low air loss bladder. The air volume is generally small due to the small space separation between the patient and the top portion of the device. An intermediate pressurized rigid bladder supports the patient. The lower high air loss bladder serves to create an air cushion that allows the patient on the device to be moved easily. The low air loss bladder locally ‘floats’ the patient off the mattress surface. Moreover, the low air discharge air bladder does not provide heated air and does not have sufficient air delivery capacity to surround the area around the patient with warm air.
U.S. Pat. No. 5,561,873 to Weedling discloses an air chamber-type patient mover air pallet with multiple control features. The air chamber-type patient mover air pallet does not have separate upper and lower chambers disconnected from each other, the first chamber providing controlled heated or cooled air surrounding the patient for temperature control while a second separated chamber having adequate air flow provides an air cushion for easy transverse movement of a patient.
U.S. Pat. No. 5,590,428 to Roter discloses an air pressurized person supporting device with ventilation. The upper wall is formed with a plurality of openings at spaced locations receiving a plurality of valve members. Valves in the supporting device seal off everywhere except where the person applies pressure, providing ventilation of air. Since no air is released under the support device, there is no air cushion, and the device does not function to lift or transport. Further, the device does not provide heated air surrounding the patient.
U.S. Pat. No. 5,652,987 to Fujita discloses a decubitus ulcer prevention device. This decubitus ulcer prevention device comprises an air generator with a fan and an air mattress for receiving air from the air generator. Air is discharged at a surface through minute air discharge holes. Along a flow path of the air that passes through the fan are located, in order as named, a heater and an alkaline chlorine dioxide gas generator, in which is internally provided a ceramic body that is impregnated with an alkaline chlorine dioxide solution. Air that is heated, by passing through the heater, is brought into contact with the ceramic body, so that air that includes alkaline chlorine dioxide gas is thus supplied to the air mattress. The decubitus ulcer prevention device delivers heated air or ambient air treated with chlorine dioxide through fine apertures on the skin contacting surface of an air mattress. This complex system is not a transfer device; air is not delivered on the underside of the air mattress and the air mattress with the supported patient may not be easily displaced in a transverse direction. The device is not designed to be disposable.
U.S. Pat. No. 5,781,943 to Moenning et al. discloses a medical table and method for moving a patient from a first position to a second position. This medical table includes a base. The medical table with roller support uses a motor to rotate the rollers to change the position of the patient. No air is delivered on the bottom surface of the medical table. The lateral movement of the patient is not accomplished by the movement of an air mattress. Instead, the patient is driven by rollers and a belt under the patient, and has to be assisted by medical personnel for proper placement. Once the patient leaves this medical table, the patient has to be moved manually, causing hardship to the patient.
U.S. Pat. No. 6,073,291 to Davis discloses an improved inflatable medical patient transfer apparatus having a combination of transverse partition members and a raised perimeter section that reduces deleterious ballooning and uneven inflation as well as quick emergency deflation and provides additional security for a patient supported upon such transfer apparatus. Additional differentially inflatable patient rolling chambers are preferably supplied on the top of the transfer apparatus to provide assistance to medical personnel in beginning to roll patients reclining or lying upon the transfer apparatus, particularly in a deflated condition on a hospital bed. An improved air inlet arrangement is also provided along with certain indicia upon the surface of the transfer apparatus to expedite use by hospital personnel. The inflatable apparatus includes a top chamber having a raised peripheral chamber containing partition members, and the inside of the chamber includes partition members. As a result, the surface is not flat and the inner partition members result in a device that is cumbersome and bulky when compressed, causing discomfort to the patient. The raised peripheral chamber and partition members result in greater volume in the chamber, in turn causing greater air flow to be needed.
U.S. Pat. No. 6,065,166 to Sharrock discloses a support cushion for a person in a lateral decubitus position, comprising a base, two lateral structural supports, and a central concavity. The lateral supports are sufficiently stiff to resist rolling of the person, while the central concavity distributes the weight of the person. The device is a holder—a support cushion designed to hold the patient still while the patient is on the operating table. It is not designed for or applicable to patient transfer, and does not involve a heating or temperature control element.
U.S. Pat. No. 6,546,576 to Lin discloses structure of a ventilated mattress with cooling and warming effect. This structure of a ventilated mattress with cooling and warming effect comprises a mattress body, a warming/cooling air-delivery controlling box, and a connecting tube. The control box produces warming/cooling air to the mattress body via the connecting tube and the warming/cooling air is released via a plurality of ventilation buttons mounted at the surface of the mattress body. Thereby, the mattress provides the user with a warming/cooling effect. The mattress is not an air mattress, but has conventional springs to support a patient positioned on the mattress. No air is delivered at the bottom surface of the mattress. Due to the absence of an air cushion at the bottom surface of the mattress, a patient lying on the mattress may not be laterally moved with ease.
U.S. Pat. No. 7,090,692 to Augustine et al. discloses a thermal blanket. The blanket lies above the patient, rather than below. This thermal blanket includes an inflatable covering with a head end, a foot end, two edges and an undersurface. The covering is inflated through an inlet at the foot end by a thermally-controlled inflating medium. An aperture array on the undersurface of the covering exhausts the thermally-controlled inflating medium from the covering. When inflated, the thermal blanket self-erects and provides a bath of thermally-controlled inflating medium to the interior of the erected structure. The blanket has an aperture free top surface and a side facing the patient is provided with a plurality of apertures to discharge warm air that is supplied to the blanket. Furthermore, nothing in the device facilitates lateral movement of the patient; it is not a transfer device.
U.S. Pat. No. 7,114,204 to Patrick discloses a method and apparatus for transferring patients. This patient transfer apparatus includes an inflatable mattress, alternatively having a rigid top board with a patient restraint system on which a patient can be placed, when patient immobilization is required. A portable cart is included with a chamber for storage of a plurality of mattresses. The cart also has a gas/air blower and power supply system for empowering the blower. Pressurized air is supplied to a single chamber of an air mattress, which discharges the air through the underside of the mattress, and not independently into an upper or lower chamber. While this passage of air creates an air cushion under the mattress, permitting lateral displacement of the patient, there is no indication that the pressure of supplied air is regulated. No warm air is delivered to the patient positioned on the upper surface of the mattress device, and patient temperature is not controlled.
U.S. Pat. No. 7,627,910 to Davis discloses a transfer mattress including an upper mattress having three longitudinally oriented plenums and three separate inlet/outlet valves that are each arranged in airflow communication with their respective plenum. First and second of the plenums are arranged in airflow communication with one another while a central plenum is arranged in airflow isolation from the first plenum and the second plenum so that the first and second plenums may be inflated and deflated independently of the central plenum. A lower inflatable mattress is separated by a common wall from the upper mattress. A lower inlet/outlet valve is arranged in airflow communication with a lower plenum defined by the lower inflatable mattress. A bottom wall defines a plurality of perforations so that when the lower plenum is charged with pressurized air, it escapes under pressure through the perforations to create an air bearing under the mattress. A method for transporting a patient in comfort is also provided by the invention. The inflatable apparatus includes a top chamber having raised peripheral chamber containing partition members, and the inside of the chamber includes partition members. As a result, the surface is not flat and the inner partition members result in a device that is cumbersome and bulky when compressed, causing discomfort to the patient. The raised peripheral chamber and partition members result in greater volume in the chamber, in turn causing greater air flow to be needed.
U.S. Pat. No. 7,278,179 to Schneider describes an inflatable mat with vent structures controlled by heat sensors. It is used to treat skin breakdown. It is not a transfer device and no air is expelled from the lower surface. Heat serves only to change the chemical structure of the upper surface to allow air to circulate to the skin. The device is not used in an operating room or designed to maintain body temperature.
U.S. Pat. No. 7,565,709 to Davis discloses a double chambered transfer mattress capable of partial deflation, and which includes a top inflatable mattress and a bottom inflatable mattress that are separated by a common wall from one another. A selectable inlet/outlet valve is arranged for airflow communication between an interior chamber of the bottom inflatable mattress and a source of pressurized air. A one-way valve is positioned through the common wall so as to provide selective air flow communication between the top inflatable mattress and the bottom inflatable mattress. When the inlet/outlet valve is closed, air continues to escape from perforations in the bottom inflatable mattress, and the one-way valve is actuated so as to prevent deflation of the top inflatable mattress. The inflatable apparatus includes a top chamber having raised peripheral chamber containing partition members, and the inside of the chamber includes partition members. As a result, the surface is not flat and the inner partition members result in a device that is cumbersome and bulky when compressed, causing discomfort to the patient. The raised peripheral chamber and partition members result in greater volume in the chamber, in turn causing greater air flow to be needed.
U.S. Pat. No. 7,735,164 to Patrick discloses a disposable patient transfer mattress including a rectangular top sheet, a rectangular bottom sheet, internal baffles, and a receptacle configured to receive a connector for supplying air to inflate the mattress. The bottom sheet corresponds to the top sheet, and the periphery of the bottom sheet is joined to the periphery of the top sheet. The internal baffles extend between the top sheet and the bottom sheet. Each baffle is a rectangular sheet with first and second parallel edges, and each baffle is joined to the top sheet along the first edge and to the bottom sheet along the second edge. The bottom sheet has a plurality of holes configured to provide a continuous cushion of air under the mattress when the mattress is inflated. The top sheet, bottom sheet, and internal baffles are made of fabric backed with a thermally weldable material, where the thermally weldable material faces the interior of the mattress for facilitating thermal welding of the baffles to the top surface and the bottom surface. Pressurized air is supplied to a single chamber of an air mattress, which discharges the air through the underside of the mattress, and not independently into an upper or lower chamber. While this passage of air creates an air cushion under the mattress, permitting lateral displacement of the patient, there is no indication that the pressure of supplied air is regulated. No warm air is delivered to the patient positioned on the upper surface of the mattress device, and patient temperature is not controlled.
U.S. Pat. No. 7,914,611 to Vrzalik discloses a support system including a multi-layer cover sheet with a number of layers. In certain embodiments, a source to move air inside and outside the multi-layer cover sheet can be provided. The source can include a source of positive pressure or negative pressure. The mattress is not a transfer device, does not have air vents below or above, and has no temperature regulating action.
U.S. Pub. Pat. App. No. 2008/0000030 to Wang discloses an inflatable mattress designed for more than one body to be supported on its surface. The mattress is not a transfer device, does not have air vents below or above, and has no temperature regulating action.
U.S. Pub. Pat. App. No. 2009/0320211 to Lau discloses an inflatable bed assembly having a plurality of inflatable cushion cells disposed on the top of the inflatable bed. Each cushion cell has a vent fluidly interconnecting the interior volume of the cushion cell with a main air chamber of the bed. When the bed is inflated, the cushion cells inflate and form raised projections on the top of the bed. The cushion cells provide a pressure sensitive surface which molds to the user's body for increased comfort. The vents are sized to allow the cushion cells to inflate upon inflation of the main air chamber, partially deflate when pressure is applied, and re-inflate when the pressure is removed. The size of the vents dampens the rate that air passes through the vent. The controlled inflation and deflation of the cells softens the impact caused by application of a body thereon and simulates the dampened response of “memory-foam”. The mattress is not a transfer device, does not have air vents below or above, and has no temperature regulating action.
Foreign Patent Publication No. JP2002000669 to Masato et al. discloses a bed and chair for nursing and care. The bed or chair is lifted upwards by pumping air into an air pad. No air is delivered at the bottom of a mattress to create an air cushion that facilitates movement of a patient. This '669 merely raises a bed or a chair.
“AirMatt—Patent Transfer System” at web location http://www.midmed.com.au/index.php?module=pagesetter&func=viewpub&tid=2&pid=55& header=1 discloses Airmatt|Lateral Air Transfer System. The AirMatt system only provides air at the bottom surface of the mattress for easy displacement of a patient. No heated air is delivered from the top surface of the mattress for temperature control during surgery and the mattress is not disposable.
“AirPal—Patient Air Lift” at web location http://www.airpal.com/manual1.pdf discloses a patient transfer system. The AirPal—Patient Air Lift has a mattress on which the patient is positioned. Air is supplied to the mattress to enable the lateral movement of the patient, who floats on an air cushion. The mattress is not moved. Rather, the floating patient is moved. No warm air surrounds the patient.
“Hover Tech International—HoverMatt” is found at web location http://www.hovermatt.com/. The brochure is available at http://www.hovermatt.com/media_pdf/HoverMatt_Brochure.pdf. It discloses the HoverMatt® Air Transfer Mattress. The HoverMatt provides air directly under the patient forming an air cushion so that the patient can be laterally slid on the mat. There is no air provided on the bottom surface of the mat forming an air cushion. The mat is not laterally slid. Instead, the patient is slid by an attendant. No warm air surrounds the patient.
None of the devices described hereinabove teaches or discloses a dual function patient lifter with temperature control. temperature control devices described are associated with heavy mattresses. The thick supporting structures are designed for longer term or continuous usage, and not for the short term, transient application of patient transfer. Further, none of the devices provides an inter-operative pad that delivers filtered clean air to surround the patient. Most of the devices are not practical for single usage and disposal.